Cu^(2+)/TiO_2-SiO_2催化剂的制备及其光催化降解气相间二甲苯的性能

Preparation of Cu^(2+)/TiO_2-SiO_2 Catalyst and Its Photocatalytic Activity for Degradation of m-Xylene in Gaseous-Phase

以钛酸丁酯、正硅酸乙酯和硝酸铜为主要原料,采用溶胶-凝胶法制备了Cu2+/T iO2-S iO2催化剂,分别用X射线衍射、BET比表面积测试、透射电子显微镜、紫外-可见光谱和傅里叶变换红外光谱对其进行了表征;以间二甲苯为代表物,评价了Cu2+/T iO2-S iO2催化剂对气相挥发性有机物的光催化降解活性,并讨论了复合S iO2和掺杂Cu2+的Cu2+/T iO2-S iO2催化剂对光催化降解间二甲苯活性的影响。实验结果表明,在500℃煅烧后的Cu2+/T iO2-S iO2催化剂呈锐钛矿结构,粒子分布均匀,平均粒径为9nm,比表面积为285m2/g;掺杂Cu2+促进了Cu2+/T iO2-S iO2催化剂对可见光的吸收,显著提高了光量子效率。用Cu2+/T iO2-S iO2催化剂光催化降解质量浓度100m g/L的气相间二甲苯,反应240m in后,间二甲苯的降解率达96.4%。

Cu^2＋/TiO2-SiO2 catalysts were prepared by sol-gel method from tetrabutyl titanate, n-ethyl metasilicate and cupric nitrate. Properties of the catalyst were characterized by means of X-ray diffraction （ XRD）, Brunauer Emmett Teller （ BET ）, transmission electron microscopy （ TEM ）, UV-Vis adsorption spectroscopy and Fourier transform infrared spectroscopy （FFIR）. Experiments of photocatalytic degradation of m-xylene as probe compound in gaseous-phase were carded out to evaluate the photocatalytic activity of the catalyst. Effects of adding SiO2 and Cu^2＋ to photocatalytic activity of Cu^2＋/TiO2-SiO2 were investigated. Cu^2＋/TiO2-SiO2 catalysts were of anatase crystalline structure, and their average particle diameter and specific surface area were 9 nm and 285 m^2/g respectively after heat treatment at 500 ℃. Adding Cu^2＋ to TiO2-SiO2 improved adsorption efficiency for visible-light. Photocatalytic degradation conversion of m-xylene （ 100 mg/L） in gaseous-phase on Cu^2＋/TiO2-SiO2 catalyst could reach 96.4% under ultraviolet light for 240 min.